Migrate to cargo_embargo. am: 3e1c42f469 am: bbe624c5a7 am: f6cb32d216

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/fnv/+/2796414

Change-Id: I6c582fcd21d96af07edcf925ad5fc965e523f04e
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>